The present invention relates to massaging devices and especially to massaging chairs adapted to give a continuous rubbing or rolling motion to the back or other portion of the user's body.
In the past, a great variety of massaging devices have been provided, including hand and individual massages, but the massaging devices most closely associated with the present invention are massaging and therapeutic chairs and tables. A typical massaging chair might include a vibratory mechanism having a plurality of wheels chain mounted to run up and down a track located behind the front cushioning of the chair back as illustrated in U.S. Pat. No. 3,322,116 for a vibratory massage apparatus. Another type of therapeutic chair uses transducers to generate vibratory frequencies in the frame of the chair as illustrated in U.S. Pat. No. 3,556,088. U.S. Pat. No. 2,790,440, a variable pressure cushion is shown having a plurality of slats interconnected with hinges and mounted to a framework which is connected to electric motors driving worm gears to move the slats. More typical is U.S. Pat. No. 3,628,528, for a massaging and reducing machine which has a roller riding on a track and driven by an electric motor riding under a belt which moves the belt as the roller moves by. In U.S. Pat. No. 3,298,363, an apparatus with an adjustable body support member is provided, while in the Portumus massaging apparatus of U.S. Pat. No. 2,827,044, an electric motor drives a rotating cylindrical shaft having a cam groove therein found in a double helix with a cam follower following the groove back and forth, similar to the operation of a line guide on a fishing reel. U.S. Pat. No. 3,656,190 illustrates a body support having a cover and a plurality of spring loaded members thereunder while the massage couch of U.S. Pat. No. 3,207,152 has an electric motor driving shafts to manipulate circular pads of foam rubber protruding through the center portion of a bench or table. The massaging chair of U.S. Pat. No. 3,653,375 has electric motors with an eccentric weight mounted thereon adjacent to the frame of the chair so that actuation of the motors will produce a vibratory action in the frame and chair.
In contrast, the present invention provides a simple positive massaging action in a chair which utilizes support slats as the cam followers which are driven by an elongated helical cam formed by a steel, plastic, or aluminum bar, or the like, wrapped around an elongated shaft which is driven by an electric motor and thereby provides a continuously variable movement of the slats mounted under the cushioning cover material of the chair providing a uniform and continuous backrub.